Apparatus for braking rolled bars to rest on the cooling bed of a bar mill

ABSTRACT

An apparatus is disclosed comprising a movable base mounted on a support and so arranged that its rear part, in the direction of the bar travel, carries a brake hold-down holding the bar against supporting means whereas on its front part is mounted arresting means clamping the bar between the supporting means and the movable base support, the arresting means being adapted to clamp the tail end of the bar when the latter while still in forward motion goes out of contact with a clamping member. The invention is aimed at reducing scrap metal losses in lining up the ends of rolled bars in &#39;&#39;&#39;&#39;a batch&#39;&#39;&#39;&#39; prior to their cutting to length.

Vasiliev et al.

APPARATUS FOR BRAKING ROLLED BARS TO REST ON THE COOLING BED OF A BAR Evgeny Mikhailovich Vasiliev, 75 kv. 137 prospekt Vorontsova; Vladimir Sergeevich Egorov, prospekt Gagarina, 2 kv. 12; Jury Nikolaevich Kovalenko, ulitsa Dnepropetrovskaya, 10g, kv. 78, all of Dnepropetrovsk; Mikhail Ivanovich Kostjuchenko, ulitsa Tramvainaya, 1 1, kv. 20, Krivoi Rog; Anatoly Vasilievich Litvin; Grigory Gavrilovich Pobegailo, both of prospekt K. Marxa, 53a, kv. 5, Dnepropetrovsk; Vladimir Mikhailovich Churakov, ulitsa Revoljutsionnaya, 12, kv. 24, Krivoi Rog; Alexandr Nikolaevich Lensky, prospekt Gagarina, 98, kv. 10, Dnepropetrovsk; Viktor Vladimirovich Ostapenko, ulitsa, Lenina 35, kv. 26, Krivoi Rog; Anatoly Vladimirovich Prazdnikov, ulitsa Uritskogo, 1 1, kv. 22, Dnepropetrovsk; Ivan Sergeevich Sidorov, ulitsa Revoljutsionnaya, 8, kv. 24; Boris Vladimirovich Khovrin, ulitsa Revoljutsionnaya, 9, kv 39, both of Krivoi Rog; Ljud-mila Petrovna Fabrika, prospekt Ilicha l7, kv. 16, Dnepropetrovsk, all of USSR.

to length.

Filed: Nov. 15, 1972 Appl. No.: 306,821

References Cited UNITED STATES PATENTS 3/1972 Shah 188/65! 8/1966 Hundertmark et a1 198/127 R 12/1970 Buchheit 198/127 R Primary Examiner-Milton S. Mehr Attorney, Agent, or Firm-Holman & Stern ABSTRACT An apparatus is disclosed comprising a movable base mounted on a support and so arranged that its rear part, in the direction of the bar travel, carries a brake hold-down holding the bar against supporting means whereas on its front part is mounted arresting means clamping the bar between the supporting means and the movable base support, the arresting means being adapted to clamp the tail end of the bar when the latter while while still in forward motion goes out of contact with a clamping member. The invention is aimed at reducing scrap metal losses in lining up the end of rolled bars in a batch prior to their cutting 4 Claims, 3 Drawing Figures PATENTEDMAY 14 mm SHEET 1 0F 2 UYHENTED MAY 14 I974 SHEET 2 BF 2 APPARATUS FOR BRAKING ROLLED BARS TO REST ON THE COOLING BED OF A BAR MILL BACKGROUND OF THE INVENTION This invention relates generally to the production of rolled bar stock and more particularly it relates to an apparatus for braking rolled bars to rest on the cooling bed of a bar mill.

An apparatus has previously been proposed for braking rolled bars to rest on the cooling bed of a bar mill comprising a brake hold-down arranged on a movable base mounted on a support, supporting means against which the hold-down presses the bar during its slowing down after it has been kicked off a roller table and traversed to the supporting means, and a drive to make the brake holddown inoperative after the bar has been fully brought to rest (See, for instance, USSR authors certificate No. 155,473, cl. B2lb, 7a, 26/02).

This well known apparatus consists of a shoe fastened to a tie rod moving along an arc and pressing by its own weight the bar against a lifting valve with the aid of which the bar is swept off a roller table into a straightening pocket of a cooling bed.

Device of this type, however, are designed to only reduce the distance and the time required for bringing the bar to rest. They do not provide for fixing precisely the bar in position after it has been fully braked to rest. As a result, the tail ends of successive bars are not disposed in a straight line normal to the direction of the .bar movement across the bed. The scatter-of the tail ends and, consequently, that of the front ends (a maximum distance between the ends of successive bars) determine the metal cutting losses since prior to the cutting-to-length of rolled bars collected in batches, the bar front and tail ends must be lined up by common cuts on a shear.

Moreover, braking by means of a shoe results in damaging the bar surface over a considerable length.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to overcome the above noted disadvantages.

The principal object of the present invention is to provide such an apparatus for braking rolled bars to rest on the cooling bed of a bar mill which will make it possible to more efficiently slow down the forward motion of the tail ends of successive bars and ensure stopping of the bar over a shorter stopping distance.

It is therefore an object of the present invention to provide such an apparatus for braking rolled bars to rest on the cooling bed of a bar mill which will make it possible to more efficiently slow down the forward motion of the tail ends of successive bars and ensure stopping of the bar over a shorter stopping distance.

The above mentioned and other object of the invention are accomplished by proposing an apparatus for braking rolled bars to rest on the cooling bed of a bar mill comprising a brake hold-down arranged on a movable base mounted upon ,support, supporting means against which the bar is held by the brake hold-down during slowing down the forward motion of the bar after it has been thrown off a roller table and has traversed to the supporting means, and a drive to disengage the brake hold-down after the bar has been fully braked to rest. According to the invention, a part of the movable base located from the side of the support functions as arresting means causing the bar to be clamped between the movable base support and the supporting means, the clamping member of the arresting means being located behind the brake hold-down in the direction of the bar travel so that upon disengagement of the brake hold-down from the bar the clamping member of the arresting means is pressed against the latter and thus the bar is braked to rest due to the action of a clamping force arising under the influence of the inertia forces of the bar advancing in a longitudinal direction.

It is preferable to arrange the arresting means so that during the brake hold-down being kept in contact with the bar, between the clamping member of the arresting means and the bar a clearance is maintained due to which upon disengagement of the brake hold-down from the bar the clamping member of the arresting means comes in contact with the bar whereby providing clamping of the bar tail end by the arresting means between the movable base support and the supporting means against which the bar is pressed during braking thereof to rest.

It is also preferable that the movable base be provided in the form of a four-bar mechanism the movable portion of which accommodates the brake hold-down and the clamping member of the arresting means thus ensuring stable clamping of the bar tail end by the arresting means within a wide range of bar thicknesses.

BRIEF DESCRIPTION OF THE DRAWING The invention will be hereinafter described in detail taking by way of example some embodiments thereof and with reference to the accompanying drawings in which:

FIG. 1 is a skeleton diagram of an apparatus for braking rolled bars to rest on the cooling bed of a bar mill illustrating its four operating positions l-IV; and

FIGS. 2 and 3 show an embodiment of the invention with the apparatus located below the straightening pocket.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The apparatus consists of a movable base 1 at the end of which, from the side wherefrom a bar 2 enters (the direction of the bar travel is shown by an arrow), is mounted a brake hold-down having the form of an idle roll 3. On the base 1, behind the brake hold-down in the direction of the bar travel is located a clamping member 4. The movable base 1 is connected by means of a hinge 5 with an adjusting spring mechanism 6 mounted on a support 7 and is also pivotally connected with a displacement drive provided in the form of a piston-type pneumatic cylinder 8. The apparatus for braking rolled bars to rest on the bar mill cooling bed is installed at the beginning of the cooling bed above the first groove of a straightening pocket 9, the surface thereof being used .as supporting means during the bringing of the bar to rest.

The apparatus operates as follows. In the starting positin (FIG. 1 I), the movable base 1 with the idle roll 3 and the clamping member 4 is raised by the pneumatic cylinder 8 above the straightening pocket 9. When the bar enters the first groove of the straightening pocket, the cylinder 8 is actuated and the movable base 1 is lowered until the roll 3 comes in contact with the bar 2 which continues its forward travel in the straightening pocket (FIG. 1 II). Thus, the forward motion of the bar begins to be slowed down at a rate proportional to the force of gravity of the movable base 1 and a force exerted upon the bar by the roll 3 operated by the pneumatic cylinder 8. With this braking action the force is transmitted to the bar only via the idle roll 3 since the clamping member 4 does not contact the bar due to a clearance 8 not exceeding the bar thickness.

Upon emerging of the tail end of the bar 2 from the idle roll 3, the latter is lowered under the action of the force of gravity of the movable base I and the pressure of the pneumatic cylinder 8, aand the clamping member 4 comes in contact with the bar (FIG. 1 III). The design dimensions of the apparatus are so selected that the a angle, formed by the intersection in the fulcrum point of the hinge 5 of a perpendicular dropped therefrom to the bar surface and a straight line passing through the point of contact of the clamping member 4 with the bar, does not exceed the angle of friction between the contacting materials. Therefore, upon the clamping member 4 coming in contact with the bar the movable base 1 and the bar get clamped between the straightening pocket and the adjusting spring mechanism 6 which adjusts the clamping force which determines the bar stopping distance. A section of the movable base between the point of contact of the clamping member with the bar and the hinge 5 functions as arresting means. The scatter of the front (tail) ends of successive bars on the cooling bed depends on the stopping distance, therefore a distance between the contact points of the idle roll and the clamping member with the bar should not be greater than a tolerance for cutting the bar end.

After stopping the bar, the movable base 1 with the idle roll 3 and the clamping member 4 is returned to the starting position, and the apparatus is ready to receive the next bar (FIG. 1 IV).

With reference to FIGS. 2 and 3 an embodiment of the invention with the apparatus located below the straightening pocket is shown.

The apparatus has idle rolls l0 and 11 with vertical axes of rotation which are used to clamp the bar. The rool I0 is secured to the end ofa driven lever 12 connected with a drive for displacing the roll, provided here in the form of a pneumatic cylinder 13. At the other end of the driven lever 12 a brake shoe 14 is rigidly fixed.

The second idle roll 11 is attached to the end of a bar 16 of four-bar mechanism 17, the bar 16 being parallel to a fixed support 15. At the opposite end of this bar is mounted a block 18 with a clamping member 19. The four-bar mechanism is loaded to compression in the direction of an adjustable stop 20 by a compression spring 21.

The apparatus for braking rolled bars to rest is located at the beginning of the cooling bed above the first groove of a straightening pocket 22.

The apparatus operates in the following way. The bar 2 enters a run-in table 23 of the cooling bed, and its forward motion begins to be slowed down by throw-off mechanism 24 which via rods 25 lift the bar from the position B to the position C. Thus the bar is transferred into the first groove of the straightening pocket 22. At this moment, the spring 21 brings the four-bar mechanism 17 against the adjustable stop 20 while the idle roll 11 with the block 18 are brought forward as far as possible in the direction of the valves 24. The driven lever 12 is in its lowered position, whereas the roll 10 and the brake show 14 are in their ambushed position blow the straightening pocket (shown with a dot-anddash line in FIG. 2).

After the bar has entered the first groove of the straightening pocket (position D), the pneumatic cylinder 13 is actuated and turns the driven lever 12 until it rests against a stop 25 thereby positioning the bar 2 between the rolls l0 and 11. Simultaneously the four-bar mechanism turns compressing the spring 21 (shown with a dot-and-dash line in FIG. 3). Thus the bar is braked between the idle rolls at a rate proportional to the compression force of the spring 21. Between the clamping member 19 of the block 18 and the bar 2, there is a clearance 6, not exceeding the bar thickness.

Upon the bar tail end leaving the rolls l0 and 11, the spring 21 brings the clamping member 19 into contact with the bar. When the clamping member is pressed against the bar, the latter and the four-bar mechanism get clamped between the fixed support 15 and the brake shoe 14. The magnitude of the clamping force is controlled by the air pressure in the chamber of the pneumatic cylinder 13 and the force with which the idle rolls are pressed against the bar, by the spring 21. Thus a section of the four-bar mechanism 17 between the point of contact of the clamping member 19 with the bar and a fulcrum point 27 functions as arresting means.

After stopping of the bar, the driven lever 12 is positioned by the pneumatic cylinder 13 below the straightening pocket. The spring 21 forces the four-bar mechanism against the stop 20 somewhat displacing the bar in the direction of the throw-off valves 24. After the bar has been discharged into the next groove of the straightening pocket, the apparatus is ready to start operation anew.

The scatter of the tail (front) ends of rolled bars when using this braking procedure is considerably less than with the application of the well known device mentioned above and does not exceed the distance between the points of contact of the idle roll 3 and the clamping element with the bar 2 being selected in accordance with a tolerance on cutting the bar end.

Due to the presence of the two idle rolls clamping the bar until the tail end is arrested, all possibility is eliminated of damaging the bar surface over its entire length except the tail end which is to be cut off. In its interaction with the adjustable stops 20 and 26 the four-bar mechanism 17 enters the stability of operation of the apparatus within a wide range of bar thickness due to the constant value of the clearance 6 and that of the angle of clamping.

What we claim is:

1. An apparatus for braking rolled bars to rest on the cooling bed of a bar mill, said apparatus comprising a movable base mounted on a support; a brake holddown located on said movable base; supporting means against which the bar is held by said brake hold-down during slowing down of the bar forward motion after it has been thrown off a roller table and has traversed to said supporting means; a part of said movable base located from the side of said support and functioning as arresting means causing the bar to be clamped between said support of the movable base and said supporting means, a clamping member of the arresting means being located behind said brake hold-down in the direction of the bar travel so that upon disengagement of the brake hold-down from the bar, the clamping member of the arresting means is pressed against the latter and thus the bar forward movement is slowed down due to the action of a clamping force arising under the influence of the inertia forces of the bar advancing in a longitudinal direction; and drive means for disengaging said brake hold-down.

2. An apparatus for braking rolled bars to rest as claimed in claim 1, wherein the arresting means is so arranged that when the said brake hold-down contacts the bar there is a clearance between said clamping member of the arresting means and the bar, due to which clearance upon disengagement of said brake hold-down from the bar said clamping member of the arresting means comes in contact with the bar end clamps it.

3. An apparatus for braking rolled bars to rest as claimed in claim 1, wherein said movable base is provided in the form of a spring-loaded four-bar mechanism having mechanism support and supporting means, the movable part of which accommodating said brake hold-down and said clamping member of the arresting means so that upon the bar going out of contact with said clamping member, said spring brings the clamping member into contact with the bar, thereby the latter and said four-bar mechanism are clamped between the mechanism support and the supporting means.

4. An apparatus for braking rolled bards to rest as claimed in claim 1, wherein said supporting means against which the bar is held during slowing down its forward motion is located on a driven lever retracted together with said supporting means by means of said drivemeans from the path of the bar travel across the rolling bed after the bar has been fully braked to rest. 

1. An apparatus for braking rolled bars to rest on the cooling bed of a bar mill, said apparatus comprising a movable base mounted on a support; a brake hold-down located on said movable base; supporting means against which the bar is held by said brake hold-down during slowing down of the bar forward motion after it has been thrown off a roller table and has traversed to said supporting means; a part of said movable base located from the side of said support and functioning as arresTing means causing the bar to be clamped between said support of the movable base and said supporting means, a clamping member of the arresting means being located behind said brake hold-down in the direction of the bar travel so that upon disengagement of the brake hold-down from the bar, the clamping member of the arresting means is pressed against the latter and thus the bar forward movement is slowed down due to the action of a clamping force arising under the influence of the inertia forces of the bar advancing in a longitudinal direction; and drive means for disengaging said brake hold-down.
 2. An apparatus for braking rolled bars to rest as claimed in claim 1, wherein the arresting means is so arranged that when the said brake hold-down contacts the bar there is a clearance between said clamping member of the arresting means and the bar, due to which clearance upon disengagement of said brake hold-down from the bar said clamping member of the arresting means comes in contact with the bar end clamps it.
 3. An apparatus for braking rolled bars to rest as claimed in claim 1, wherein said movable base is provided in the form of a spring-loaded four-bar mechanism having mechanism support and supporting means, the movable part of which accommodating said brake hold-down and said clamping member of the arresting means so that upon the bar going out of contact with said clamping member, said spring brings the clamping member into contact with the bar, thereby the latter and said four-bar mechanism are clamped between the mechanism support and the supporting means.
 4. An apparatus for braking rolled bards to rest as claimed in claim 1, wherein said supporting means against which the bar is held during slowing down its forward motion is located on a driven lever retracted together with said supporting means by means of said drive means from the path of the bar travel across the rolling bed after the bar has been fully braked to rest. 